There are many diseases and conditions that affect the posterior segment of the human eye which can lead to a decrease in visual acuity and eventually blindness. Deleterious consequences from disease processes or physio-anatomic defects can affect the tissues of the back of the eye such as the sensory retina, the retinal pigment epithelium (RPE) and the choroid. Diseases such as age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity, choroidal neovascularization, retinitis and macular edema; and conditions such as macular holes, retinal detachments, epiretinal membranes, retinal or choroidal venous occlusions can all lead to vision loss that ranges from mild to total. Many of these ailments are treated through systemic or intravitreal injections of pharmaceutical agents, or via surgery through the vitreous cavity. Procedures such as macular translocation, RPE cellular and tissue transplants or even the placement of retinal implants are new techniques and technologies that require minimally invasive access to posterior tissues in order for the treatments to be applied at site specific locations.
Interventional procedures targeting tissues beneath the sensory retina are difficult to perform due to limited accessibility and the delicate structure of the retina which can be easily damaged during surgical manipulation. It is desired to provide a means of accessing and delivering therapies in a safe manner to the tissues that are not directly accessible via the vitreous cavity. Accessing the sub-retinal space, using delicate traction to hold the sensory retina, would allow for the safe and direct intervention to tissues adjacent to the sub-retinal space including the outer nuclear or photoreceptor layer of the retina and the RPE.
The present invention is directed to surgical devices that can advantageously provide sub-retinal access through an ab-interno approach, by maintaining position on, and protecting the retina while creating and maintaining a patent sub-retinal space of sufficient size to introduce and perform treatment.